The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. However, these advances have increased the complexity of processing and manufacturing ICs and, for these advances to be realized, similar developments in IC processing and manufacturing are needed. In the course of integrated circuit evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometry size (i.e., the smallest component (or line) that can be created using a fabrication process) has decreased.
The ever-shrinking geometry size brings challenges to semiconductor fabrication. For example, photoresist masks may be more prone to the effects of capillary forces. This is exacerbated as the aspect ratio of the mask increases and/or as the pitch decreases. As a result, photoresist masks may collapse, for example due to being pulled by capillary forces between adjacent photoresist masks.
Therefore, while existing semiconductor fabrication technologies have been generally adequate for their intended purposes, they have not been entirely satisfactory in every aspect.